Irish rugby welcomed Europe with open arms yesterday but will promptly turns its back to the continent in less than 48 hours.

And with good reason. The derby between Munster and Leinster may still be classed as the biggest in world rugby but it has been fighting for its credibility of late. It needs a resurgence and, for that to happen, both sides need to be resurgent.

The signs are positive, despite Irish sides being even more enthusiastic about a European exit than the Tories of late. That both its participants flopped in Europe last season contributed to the declining public interest in the derby; and the absence of this fixture from their severely undercooked European warm-up schedule damaged Leinster even more than it did Munster.

Strange to think that it is only just over a decade ago since we could hang over the railings in the old Donnybrook and trade insults with O'Kelly and O'Connell at lineout time; and then there was even one season when they didn't stage the fixture at all!

While everyone talks about the famous Christmas Celtic League final of 2001, it was really ten years ago this month that the whole shebang kicked off in earnest when 27,000 turned up for a league game in the RDS.

To borrow from PJ Mara, now it was showtime! Two epic Heineken Cup semis within three years; Croke Park the zenith, a world record crowd.

Yet the sold-out signs have gathered dust in Limerick and Dublin since then; nevertheless, sales approaching 40,000 for a lunchtime clash this Saturday should never be sniffed at and, with both sides on an upswing, this fixture might be in for a timely fillip. And with it their respective hopes for wiping last year's European flop from the memory.

Maybe it takes an outsider to remind us what we've been missing.

"It's probably one of the biggest things I missed going back to New Zealand," says Leinster captain Isa Nacewa. "The thought of not being involved in another Leinster-Munster game. It starts on the Monday and just builds itself.

"The intensity in training, the added dimension that these guys were in camp together on Monday and then they'll be ready to get stuck into one another a few days later.

"It's a beautiful week. So much history and you feel that even in the training. It's better than it was last year. We're both in good form and it's the game you need before Europe.

"I've been part of some great occasions and I think this one will be just as good. It's a game you want to be involved in."

Ireland's camp rudely interrupted proceedings this week - many of the adversaries, like Peter O'Mahony and Jack McGrath, roomed together - but it may stoke the flames of conflict.

"It's pretty unique!" laughs coach Leo Cullen, who drummed his fingers on Monday hoping all his troops would survive intact. "It adds to the rivalry and hopefully that's what the crowd gets behind as well, that they see 15 guys from either side of the split in the camp going full on against each other. All the players know what's at stake because of what's coming up as well. Everyone wants to be picked for the two European games, which leads into Tests against New Zealand twice, Australia and Canada. There's a lot at stake for everybody."

Irish rugby once fed off this fixture and may do so again. "It just evolves, new characters," says Cullen. "You're waiting to see who will emerge."

It is debatable whether both can meet again in the last four of Europe and spark such hype as visited upon Croke Park in 2009. Nacewa, who was there, is convinced it can. "Absolutely. Why not? I can't speak for Munster but we are heading in the direction that we want to." The season truly starts in earnest this weekend.